The present disclosure is directed to an apparatus for handling pipe and especially heavy pipe which is normally denoted as casing. During the drilling of a well, the typical pipe size used in the drill string is about five inches or so. Smaller pipe is used in a well including two and three-eighths inch tubing which is placed in the well as a completion step to serve as a flow line extending to the surface. Larger pipe however is also used to complete a well, and in particular, at the casing stage, large pipe, nine inches or greater, may be placed in the well. The casing which is placed in the well is heavy because it is quite large in diameter. It is not uncommon for a joint of casing to weigh easily as much as 4,000 pounds or more. In any event, pipe of that size must be maneuvered from a pipe storage rack adjacent to a drilling rig to a position upright in the drilling rig.
The present apparatus is a system which provides both method and apparatus accomplishing this goal and a method of moving the pipe. The pipe is initially delivered and stored at the drilling rig site in a horizontal posture. The casing must be maneuvered to an upright position under the derrick. This is a relatively dangerous sequence of events.
The present inventor provided a wireline lay down apparatus which was implemented with great success in the drilling service industry. Various and sundry types of wireline operated lay down machines have been devised and implemented. The difficulty with casing is that handling by personnel is still required. The handling by personnel of heavy joints of pipe casing involves risk to the personnel and delay as the personnel attempt to keep control over the heavy pipe. Even where tubing is being handled, there is always the risk of personal injury as a result of the size, length, and weight (even as small as it may be) of the pipe being handled. Moreover, the path of travel involves movement of the pipe from a position horizontal on the pipe racks to an upright position in the derrick. The present disclosure sets forth a mechanism which is particularly adapted for handling even the heaviest of drill pipe. That is, it is adapted for handling very heavy casing to deliver the casing to a position ready for running into the well, and all of this is accomplished substantially without human pipe handling.
The present disclosure sets forth a method of maneuvering a joint of drill pipe off the end of a pipe rack where it falls into a trolley supported trough for travel from the pipe rack area toward the rig floor. The trough stops at a registered location. At that location, it supports the upper portion of the joint of pipe extending from the top end of the trough. In this location, the pipe joint can then be grasped by a locking collar. The locking collar is pivotally mounted on a pair of duplicate, extendable hydraulic rods which controllably extend and retract. This defines a set of arms which pivotally rotate so that the pipe is manuevered out of the trough where it is inclined upwardly and rotated to an upstanding position where the pipe joint is held vertically. To this end, the present apparatus utilizes a pair of duplicate extendable hydraulically operated double acting cylinders equipped with pistons and piston rods to extend the locking collar. The locking collar is maneuvered to a down position to clamp to the pipe while it is still supported in the trough. After rotation, the pipe is held in an upstanding position which is vertical with respect to the rig floor and the pipe is positioned above the rotary table. This enables the pipe to be aligned with other pipe joints previously placed in the well. This also enables the cylinders which are extended to a maximum height above the rig floor to be lowered so that the pipe is then stabbed into the casing string supported in the rotary table and thereby permits threading of the system. The elevated joint is threaded to the joints of pipe previously assembled into the casing string and it is then lowered further into the well borehole. In all instances, the pipe is mechanically handled so that human intervention is held to a minimum. This improves safety at the rig floor, and accomplishes pipe transfer much more rapidly then before. Typically, this will reduce the number of the crew handling the pipe so that crew staffing is reduced and yet speed is enhanced in handling the pipe.
While the foregoing speaks generally of the problem and describes certain aspects of the present disclosure in a rough outline, the details of this disclosure will be more readily understood on a review of the attached drawings in conjunction with the written specification found below. Moreover, the drawing set forth in apparatus, but in method or operating procedure will also be set forth so that the extremely heavy pipe including casing is transferred from the pipe storage racks adjacent to the rig to an upstanding position ready for running into a well borehole.